Cloud computing and its applications are changing the way people communicate and share information. Today, the underlying computer networks that support cloud computing and other services can consist of an enormous number of individual computers—thousands to tens of thousands of them—housed in large facilities and working in concert. These large facilities are referred to as warehouse-scale computers. As a result of their size, warehouse-scale computers require the interconnection of large numbers of computers and networking equipment (e.g., servers, switches and routers). The sheer number and scale of interconnection in warehouse-scale computers creates a need for low-cost interconnects with low power consumption and compact size.